Ligating band dispenser with a sliding deployment system

ABSTRACT

A ligating band dispenser for attachment to an endoscope having sliding elements that are positioned on the outer surface of a support structure of the ligating band dispenser. The sliding elements may be slidably engaged to the support structure. For example, the sliding elements may slide along a groove on the outer surface of the support structure. The sliding elements are advanced forward along the groove, causing the sliding elements to impact a ligating band and push the ligating band forward until it is deployed off the dispenser.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims priority to provisional application Ser. No.60/853,767 (filed 24 Oct. 2006), which is incorporated by referenceherein.

TECHNICAL FIELD

The present invention relates to medical ligating instruments and moreparticularly to medical ligating instruments that dispense ligatingbands.

BACKGROUND

Ligation is a medical procedure whereby the physician ties off ormechanically constricts a piece of body tissue with an encirclingligature such as a suture, clip, or elastic band. The purpose ofligation is to impede or obstruct the flow of blood, fluids, and otherbodily materials through the tissue. For example, the physician canremove target tissue by ligating it to obstruct all circulation throughthe target tissue, thereby causing the tissue to die and slough off.

For ligating tissue inside a body cavity, orifice, or lumen, physiciansoften use an endoscope to access the target tissue and ligate it. In onesuch form of endoscopic ligation, the physician uses the endoscope toposition a stretched elastic band over the target tissue and thenrelease the band onto the tissue so that the band contracts and catchesthe tissue. The inward pressure of the elastic band constricts thetarget tissue.

Ligating instruments have been the subject of a number of patents,including U.S. Pat. No. 5,269,789 to Chin et al.; U.S. Pat. No.5,356,416 to Chu et al.; U.S. Pat. No. 5,398,844 to Zaslavsky et al.;U.S. Pat. No. 5,857,585 to Tolkoff et al.; U.S. Pat. No. 5,853,416 toTolkoff; U.S. Pat. No. 5,913,865 to Fortier et al.; U.S. Pat. No.6,235,040 to Chu et al.; and U.S. Pat. No. RE 36,629 to Zaslavsky et al.The disclosures of these prior U.S. patents are expressly incorporatedby reference herein.

A number of ligating instruments have been developed to sequentiallydeploy multiple ligating bands. Many such ligating instruments, such asthe one disclosed in U.S. Pat. No. 5,857,585 to Tolkoff et al., rely ona trigger wire which is sequentially looped around each ligating bandand over the distal edge of the dispenser. Thus, the process ofmanufacturing such ligating band dispensers involves the steps ofsequentially weaving the wire around each ligating band and over thedistal edge of the dispenser.

SUMMARY OF THE INVENTION

In one aspect, the present invention provides a ligating band dispensercomprising: a support structure having a channel, an outer surface, aproximal end, and a distal end; at least one sliding element positionedon the outer surface of the support structure; a pull line engaged withthe at least one sliding element; and at least one ligating bandpositioned on the outer surface of the support structure distal to atleast one sliding element; wherein pulling the pull line causes at leastone sliding element to move distally with respect to the outer surfaceof the support structure, thereby causing at least one ligating band tomove distally with respect to the outer surface of the support structureand off of the distal end of the support structure.

In another aspect, the present invention provides a ligating banddispenser comprising: (a) a support structure having a channel, aproximal end, a distal end, an outer surface, and at least one slidepath on the outer surface; (b) at least one ligating band positioned onthe outer surface of the support structure; (c) a pull line adapted tobe pulled proximally for deploying the at least one ligating band off ofthe distal end of the support structure; and (d) a means for moving theat least one ligating band distally, wherein the means for moving the atleast one ligating band distally moves along the at least one slidepath.

In another aspect, the present invention provides a device for deployinga ligating band, comprising: a support structure; a pushing elementpositioned on the outer surface of the support structure; an actuatingelement for moving the pushing element; and a ligating band seatedadjacent to the pushing element; wherein actuation of the actuatingelement causes the pushing element to push against the ligating band andmove the ligating band distally along the support structure.

In another aspect, the present invention provides a method of dispensingligating bands, comprising the steps of: (a) providing a ligatingdispenser device comprising: (i) a support structure having a channel,an outer surface, a proximal end, and a distal end; (ii) at least onesliding element positioned on the outer surface of the supportstructure; (iii) a pull line engaged with the at least one slidingelement; and (iv) at least one ligating band positioned on the outersurface of the support structure distal to at least one sliding element;and (b) pulling the pull line proximally, thereby causing at least onesliding element to move distally with respect to the outer surface ofthe support structure, thereby causing at least one ligating band tomove distally with respect to the outer surface of the support structureand off of the distal end of the support structure.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of a ligating band dispenser according to afirst embodiment (shown without the ligating bands).

FIG. 2 is a longitudinal cross-section view of the ligating banddispenser of FIG. 1.

FIG. 3 is a fragmentary cross-section view of the ligating banddispenser of FIG. 2 taken along line B-B.

FIG. 4 is a fragmentary view of an alternate embodiment of the ligatingband dispenser of the present invention shown in cross-section takenalong a line similar to line B-B in FIG. 2.

FIG. 5 is a perspective view of an embodiment of a sliding element.

FIG. 6 is a side view of the sliding element of FIG. 5.

FIG. 7 is a fragmentary view of an alternate embodiment of a ligatingband dispenser shown in cross-section taken along a line similar to lineB-B in FIG. 2.

FIG. 8 is a top view of the ligating band dispenser of FIG. 1 (shownwith the ligating bands).

FIG. 9 is a side view of another alternate embodiment of a ligating banddispenser.

FIG. 10 is a top view of another alternate embodiment of a ligating banddispenser (shown without the ligating bands or sliding elements).

FIG. 11 is a top view of another alternate embodiment of a ligating banddispenser (shown without the ligating bands or sliding elements).

FIG. 12 is a cross-section view of an alternate embodiment of a slidingelement taken along a line similar to line C-C in FIG. 6.

FIG. 13 is a fragmentary side view of an alternate embodiment of aligating band dispenser shown partially in longitudinal cross-section.

FIGS. 14A-C are side views of a sliding element according to anotherembodiment (shown as it rotates forward).

FIG. 15 is a perspective view of a ligating band dispenser according toanother embodiment.

FIG. 16 is a side view of a distal portion of a ligating band dispenseraccording to another embodiment.

DETAILED DESCRIPTION

As illustrated in FIGS. 1 and 2, a ligating band dispenser 10 accordingto a first embodiment includes a substantially cylindrical housing orsupport structure 14 which has a central bore or channel 12 extendingaxially through the support structure 14. The central channel 12 is wideenough to accept tissue into the channel and allow visualization throughit, for example when the dispenser is attached to the end of anendoscope. In this embodiment, the dispenser 10 includes a flexibleconnector 17 which allows the dispenser 10 to be attached to the distaltip of an endoscope. A plurality of elastic ligating bands 15 arereceived in a stretched condition around the support structure 14.

On the outer surface of the support structure 14 is a slide path, whichin this embodiment is a groove 20 that extends from a proximal point 22on the support structure 14 to a distal point 24 on the supportstructure 14. In this embodiment, the groove 20 begins at a point closeto the proximal edge 18 of the support structure 14 and extends to thedistal edge 16 of the support structure 14.

The groove 20 engages one or more slidable displacement members orsliding elements 30 that are slidable within the groove 20. The groove20 and sliding elements 30 are adapted so that the groove 20 retains thesliding elements 30 within the groove while the sliding elements 30slide within the groove 20. As illustrated in FIG. 3, in this firstembodiment, the groove 20 and the associated portions of the slidingelements 30 are substantially in the shape of a right circular cylinder,and the groove 20 includes a shoulder 13 which retains the slidingelements 30 within the groove 20. In alternate embodiments, the grooveand sliding elements may take other shapes or dimensions that allow thesliding elements to slide within the groove while being retained withinthe groove. For example, as illustrated in FIG. 4, the groove 20′ andthe associated portion of the sliding element 30′ may take asubstantially triangle-shaped geometry. In other embodiments, the slidepath may be any other type of path upon or within which the slidingelements may slide, such as tracks, rails, or gutters.

In some embodiments, the outer surface of the support structure 14 mayalso have circumferential furrows (not shown) extending fully orpartially around support structure 14. These circumferential furrows mayserve to help seat the ligating bands onto the support structure 14.

Referring to FIGS. 3 and 5, in this first embodiment, the slidingelements 30 include a projecting element 32 that projects outwardly awayfrom the outer surface of the support structure 14. The projectingelement 32 provides an impacting surface 34 that impacts a ligating band15 and urges the ligating band forward (distally) in the direction ofarrow A (shown in FIG. 2). In alternate embodiments, the slidingelements 30 do not include a separate impacting surface on a projectingelement. Rather, the body of such a sliding element may itself beadapted and sized to provide an impacting surface that impacts aligating band, urging the ligating band forward.

The sliding elements 30 are adapted to be advanced forward (distally, inthe direction of arrow A shown in FIG. 2) as a pull line 40 is pulled.Referring to FIGS. 5 and 6, in this first embodiment, the pull line 40travels through the sliding elements 30 via a lumen or channel 38 thatextends axially within the sliding element. The pull line 40 has anengagement element such as a projection or knot 42 (seen in FIG. 6) thatimpacts the posterior (proximal) side 31 of the sliding element 30. Inthe illustrated embodiment, the knot 42 is larger than the width of thechannel 38 so that the knot 42 cannot be pulled through the channel 38and instead advances the sliding element 30.

In alternate embodiments, the sliding elements may be adapted to easilyseparate from the pull line. For example, FIG. 7 illustrates anembodiment where the sliding element 70 has a slot 36 instead of achannel through which the pull line 40 travels. The slot 36 is open onone face of the sliding element 70 to facilitate assembly of the slidingelement 70 and the pull line 40 or to facilitate disengagement of thesliding element 70 from the pull line 40. In other alternateembodiments, the pull line 40 is connected to the sliding elements byany of a number of attachment means, including tying, clamping, gluingor fastening. The pull line 40 may be a thread, filament, wire, orstring.

As illustrated in FIG. 8, in this first embodiment, slack is introducedin the pull line by slack loops or bends 44. The slack bends 44 arecoiled in the space between each sliding element 30. In an alternateembodiment, the slack bends 44 may be wedged in the space between one ormore ligating bands and the outer surface of support structure 14. Oneof skill in the art will appreciate that the slack bends 44 can bepositioned or arranged in any of a number of positions or arrangementsdesigned to store the slack bends without interfering with thefunctioning of the ligating band dispenser. Initial pulling of the pullline 40 draws up the slack so that the pull line becomes taut andfurther pulling of the pull line 40 will begin advancing the attachedsliding element 30 forward (distally). The slack in the pull line 40allows each sliding element 30 to be advanced at intervals withoutmoving other trailing sliding elements simultaneously.

Referring again to FIG. 2, in this first embodiment, a sliding element30 is positioned behind (proximal to) each of the ligating bands 15. Inoperation, the user actuates the ligating band dispenser 10 by pullingon the pull line 40. This may be done by an actuator or other meansknown in the art. After slack is drawn up, the pull line 40 advances asliding element 30, causing the sliding element 30 to impact a ligatingband 15, and urging the ligating band forward (distally) until theligating band is released from the distal edge 16 of the supportstructure 14. In alternate embodiments, the sliding elements 30 may bepositioned behind more than one ligating band 15. In one suchembodiment, as shown in FIG. 9, each groove 20 on the support structure14 may engage only a single sliding element 30. Thus, instead of havinga plurality of sliding elements, with each one being positioned behind(proximal to) each ligating band, a single sliding element 30 ispositioned behind all the ligating bands 15. In operation, pulling ofthe pull line 40 draws the sliding element 30 forward (distally), whichthen simultaneously urges all the ligating bands 15 forward (distally)so that are deployed sequentially, in intervals, as the pull line 40continues to be pulled.

In the first embodiment, the groove 20 travels linearly and parallel tothe axis of the support structure 14. In alternate embodiments, thegroove travels at an oblique angle or helically with respect to the axisof the support structure 14. For example, as illustrated in FIG. 10, thegroove 20″ may travel in a corkscrew-like pattern from a proximal pointon the support structure 14 to a distal point on the support structure14.

In this first embodiment, the support structure 14 includes a singlegroove 20. In alternate embodiments, the support structure 14 mayinclude a plurality of grooves. For example, FIG. 11 illustrates anembodiment in which the ligating band dispenser 10 has three grooves 20a-20 c. In this embodiment, each groove 20 a-20 c is engaged to its ownset of sliding elements (not shown). In another example, two grooves maybe positioned on opposite sides of the support structure with eachgroove having its own set of sliding elements. In operation, eachligating band is urged forward by the simultaneous advancement of thepair of oppositely-positioned sliding elements to facilitate symmetricaldisplacement of the ligating bands.

Once the ligating band is deployed, the subsequent disposition of thesliding element will vary according to the design of the ligating banddispenser. In certain embodiments, such as in the first embodiment shownin FIG. 2, the sliding element 30 disengages from the groove 20 as thesliding element is drawn past the distal edge 16 of the supportstructure 14. Within certain embodiments, where the sliding element isadapted to separate from the pull line (as previously described), thesliding element will dislodge from the pull line and be deposited in thebody. Depending upon its design, the sliding element may spontaneouslydislodge from the pull line after disengaging from the groove on thesupport structure, or the sliding element may be caused to dislodge byagitation induced by such acts as manipulation of the pull line, or suchevents as the sliding element colliding against a part of the ligatingband dispenser or endoscope. For example, as shown in FIG. 12, thesliding element 72 may be designed with a V-shaped slot 37 such that thesliding element spontaneously separates from the pull line 40 after thesliding element 72 disengages from the groove on the support structure.

In certain embodiments, the ligating band dispenser is adapted to rotatethe sliding element as it moves distally along the support structure.This rotation may serve various functions, including allowing the pullline to disengage from the sliding element, or reducing the slidingelement's outward projection from the surface of the support structure.In some cases, the rotation is initiated after the sliding elementdeploys a ligating band. For example, referring to FIG. 14, a slidingelement 76 may rotate as shown in the progression from frame A to B toC, causing sliding element 76 to release the pull line 40.

In another example, as shown in FIG. 14, the ligating band dispenser maybe designed such that the slotted sliding element rotates forward afterdeploying a ligating band. As illustrated in the progression from FIGS.14A to 14B to 14C, the pull line disengages from the sliding element asthe sliding element rotates forward.

In some embodiments where the sliding element dislodges from the pullline after deployment of the ligating band, the sliding element may beshaped or dimensioned to be retrieved by the operator by one or more ofvarious means. For example, the sliding element can be shaped anddimensioned to allow vacuum suction or forceps retrieval through thelumen of an endoscope.

In other embodiments where the sliding element dislodges from the pullline, the sliding element may be designed to be eliminated through thedigestive tract. In such embodiments, the sliding element may be shapedand dimensioned to avoid causing obstructions as it travels through thedigestive tract.

In yet other embodiments where the sliding element dislodges from thepull line, the sliding element may be designed to degrade within thebody and/or be absorbed by the body. For example, the sliding elementmay be formed of biodegradable polymers such as polycarboxylic acid,polyanhydrides including maleic anhydride polymers; polyorthoesters;poly-amino acids; polyethylene oxide; polyphosphazenes; polylactic acid,polyglycolic acid and copolymers and mixtures thereof such aspoly(L-lactic acid) (PLLA), poly(D,L-lactide), poly(lacticacid-co-glycolic acid), 50/50 (D,L-lactide-co-glycolide); polydioxanone;polypropylene fumarate; polydepsipeptides; polycaprolactone andco-polymers and mixtures thereof such aspoly(D,L-lactide-co-caprolactone) and polycaprolactone co-butylacrylate;polyhydroxybutyrate valerate and blends; polycarbonates such astyrosine-derived polycarbonates and arylates, polyiminocarbonates, andpolydimethyltrimethylcarbonates; cyanoacrylate; calcium phosphates;polyglycosaminoglycans; macromolecules such as polysaccharides(including hyaluronic acid; cellulose, and hydroxypropylmethylcellulose; gelatin; starches; dextrans; alginates and derivativesthereof), proteins and polypeptides; and mixtures and copolymers of anyof the foregoing.

In another embodiment of the present invention, the sliding element doesnot dislodge from the pull line after deployment of a ligating band.Rather, the sliding element continues to be drawn by the pull line andis retracted inside the central channel 12 of the support structure 14and then, optionally, through the lumen of the endoscope (not shown).

In an alternate embodiment, as illustrated in FIG. 13, the supportstructure 14 includes a groove 60 on the inner surface that iscontinuous with the groove 20 on the outer surface. The inner groove 60extends from a distal point on the inner surface of the supportstructure 14 to a proximal point on the inner surface of the supportstructure 14. In operation, after the sliding element 30 deploys aligating band (not shown) and is drawn past the distal edge 16 of thesupport structure, the sliding element 30 continues to be engaged to thesupport structure via the inner groove 60. The sliding element may thenbe retracted through the lumen of an endoscope or be dislodged from thepull line.

In yet another embodiment of the present invention, as illustrated inFIG. 15 for ligating band dispenser 90, only a single sliding element 30is situated proximal to all the ligating bands (not shown). The supportstructure 14 has a series of circumferential furrows 92 extending fullyor partially around support structure 14. These circumferential furrows92 may serve to help seat the ligating bands onto support structure 14.

In yet another embodiment, the ligating band dispenser is adapted toreduce the outward projection of the sliding element from the surface ofthe support structure as the sliding element moves distally along thesupport structure. By reducing the sliding element's outward projectionfrom the surface of the support structure, the sliding element may beconcealed, hidden, sequestered, or otherwise have its external profilereduced. For example, as shown in FIG. 16, the distal portion of thegroove 20 may increase in depth to allow sliding element 74 to becomesequestered within support structure 14 as sliding element 74 isadvanced distally. In some embodiments, groove 20 is configured so thatsequestration of sliding element 74 occurs after the ligating band isdeployed. In some embodiments, groove 20 is sloped downward such thatsliding element 74 rotates forward after deployment of a ligating band.Where sliding element 74 is slotted, forward rotation may assisted inreleasing the pull line.

The present invention has been described with respect to severalexemplary embodiments. There are many modifications of the disclosedembodiments which will be apparent to those of skill in the art. It isunderstood that these modifications are within the teaching of thepresent invention which is to be limited only by the claims.

What is claimed is:
 1. A ligating band dispenser comprising: a supportstructure having a channel, an outer surface, a proximal end, and adistal end; a groove on the outer surface of the support structure; atleast one sliding element slidably engaged to the groove on the supportstructure, wherein the groove has a shoulder that projects laterallyover the groove to retain the sliding element on the support structureas the sliding element slides within the groove; a pull line engagedwith the at least one sliding element; and at least one ligating bandpositioned on the outer surface of the support structure distal to theat least one sliding element; wherein pulling the pull line causes theat least one sliding element to move distally with respect to the outersurface of the support structure, thereby causing the at least oneligating band to move distally with respect to the outer surface of thesupport structure and off of the distal end of the support structure;and wherein the sliding element is structured to disengage the pull lineas the sliding element is drawn past the distal end of the supportstructure.
 2. The ligating band dispenser of claim 1, wherein thesupport structure has an inner surface, wherein the inner surface of thesupport structure has a groove, and wherein the groove on the innersurface is continuous with the groove on the outer surface.
 3. Theligating band dispenser of claim 1, wherein the groove extends along theouter surface of the support structure at an oblique angle to a centralaxis of the support structure.
 4. The ligating band dispenser of claim1, wherein the groove extends helically along the outer surface of thesupport structure.
 5. The ligating band dispenser of claim 1, whereinthe groove is adapted to reduce the outward projection of the slidingelement from the outer surface of the support structure as the slidingelement moves distally along the support structure.
 6. The ligating banddispenser of claim 5, wherein at least one distal point on the groove isdeeper than a proximal point on the groove.
 7. The ligating banddispenser of claim 1, wherein the sliding element comprises a slotthrough which the pull line travels.
 8. The ligating band dispenser ofclaim 7, wherein the slot is V-shaped.
 9. The ligating band dispenser ofclaim 1, wherein the sliding element is formed of a material that isbiodegradable within a body.
 10. The ligating band dispenser of claim 1,wherein the sliding element is formed of a material that is absorbableby a body.
 11. The ligating band dispenser of claim 1, wherein thesliding element rotates as the sliding element moves distally along thesupport structure.
 12. The ligating band dispenser of claim 1, whereinthe support structure further comprises at least one circumferentialfurrow that extends at least partially around the support structure. 13.The ligating band dispenser of claim 1, wherein the shoulder retains thesliding element within the groove.
 14. A ligating band dispensercomprising: (a) a support structure having a channel, a proximal end, adistal end, an outer surface, and a groove on an outer surface of thesupport structure; (b) at least one ligating band positioned on theouter surface of the support structure; (c) a pull line adapted to bepulled proximally for deploying the at least one ligating band off ofthe distal end of the support structure; and (d) a means for moving theat least one ligating band distally, wherein the means for moving the atleast one ligating band distally is slidably engaged to the groove onthe support structure, wherein the groove has a laterally-projectingshoulder that projects laterally over the groove to retain the means formoving on the support structure as the means for moving slides withinthe groove, and wherein the means for moving the at least one ligatingband distally disengages the pull line after deployment of the at leastone ligating band.
 15. The ligating band dispenser of claim 14, whereinthe means for moving the at least one ligating band distally comprisesat least one sliding element.
 16. The ligating band dispenser of claim14, wherein the means for moving is formed of a material that isbiodegradable within a body.
 17. The ligating band dispenser of claim14, wherein the means for moving is formed of a material that isabsorbable by a body.
 18. A device for deploying a ligating band,comprising: a support structure having a groove on an outer surfacethereof; a pushing element slidably engaged to the groove on the supportstructure, wherein the groove has a shoulder that projects laterallyover the groove to retain the pushing element on the support structureas the pushing element slides within the groove; an actuating elementfor moving the pushing element; a ligating band seated adjacent to thepushing element; wherein actuation of the actuating element causes thepushing element to push against the ligating band and move the ligatingband distally along the support structure; and wherein the pushingelement is structured to disengage the actuating element as the slidingelement is drawn past a distal end of the support structure.
 19. Thedevice of claim 18, wherein the actuating element comprises a pull line.20. The device of claim 18, wherein the shoulder retains the pushingelement within the groove.
 21. A method of dispensing ligating bands,comprising the steps of: (a) using a ligating dispenser of claim 1; and(b) pulling the pull line proximally, thereby causing the at least onesliding element to move distally with respect to the outer surface ofthe support structure, thereby causing the at least one ligating band tomove distally with respect to the outer surface of the support structureand off of the distal end of the support structure.
 22. The method ofclaim 21, further comprising the step of agitating the sliding elementto thereby cause the sliding element to disengage from the pull line.23. The method of claim 21, further comprising the step of rotating thesliding element to thereby cause the sliding element to disengage fromthe pull line.